First off - if mom is being a good mom she will keep babies warm. Please take away the heat lamp. It can do a lot of harm to babies. They can not regulate their heat for the first few weeks.
Secondly - have you talked to a vet? We can't do much besides offer condolences and suggestions but nothing beats a vet visit. There are so many things that can go wrong with newborn kittens.
Third - There is something called Fading Kitten Syndrome where sometimes kitties who are completely normal or deformed will simply stop eating and die. No one knows why.
http://cats.suite101.com/article.cfm...itten_syndrome
The very best thing you can do is to take these little ones to a vet asap.
